ON THE CHEMICAL CONSTITUENTS OF SOILS. 



239 



Siliceous sand, with very much magnetic iron sand 8*428 

 Earthy portion of the soil . . . . 91-572 



100000 



The aqueous infusion of the earth contained only 

 traces of common salt and gypsum, with humus, 

 lime, and magnesia. 100 parts consisted of: — 



100 000 



Manure consisting of gypsum, common salt, or 

 ashes of wood, would be highly conducive to the 

 fertility of this land. 



SOILS IN THE " MARKGRAFSCHAFT MAHREN." 



36. Surface-soil of a field very remarkable for its 

 fertility. The field is called Haargraben, and is 

 situated near the village of Nebstein. It has never 

 been manured or allowed to lie fallow and yet has 

 produced for the last 160 years the most beautiful 

 crops ; thus furnishing a remarkable example of un- 

 impaired fertility. 100*000 parts of this soil con- 

 sisted of: — 



Coarse and fine siliceous sand, with a little mag- 

 netic iron sand .... 

 Earthy matter ..... 



35-400 

 64 600 



100 000 



100 parts of the earth yielded to water 0*010 sul- 

 phuric acid, 0-010 chlorine, 0-007 soda, 0-012 mag- 

 nesia, 0-010 potash, with a little silica, humus, and 



